Swagger2 WebFlux issue: Failed to start bean 'documentationPluginsBootstrapper'... when @EnableSwagger2WebFlux is present

[pstepnowski]

Hey guys, I was spending some time trying to find out the cause but no luck.

My current setup:
kotlinVersion = '1.3.10'
springBootVersion = '2.0.2.RELEASE'

compile('org.springframework.boot:spring-boot-starter-webflux')
compile('io.springfox:springfox-swagger2:3.0.0-SNAPSHOT')
compile('io.springfox:springfox-spring-webflux:3.0.0-SNAPSHOT')

I'm getting:

2020-04-09 12:37:03,918 ERROR [main] [] org.springframework.boot.SpringApplication: Application run failed
org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NoSuchMethodError: org.springframework.plugin.core.PluginRegistry.getPluginOrDefaultFor(Ljava/lang/Object;Lorg/springframework/plugin/core/Plugin;)Lorg/springframework/plugin/core/Plugin;
	at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:184)
	at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:52)
	at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356)
	at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:157)
	at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:121)
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:885)
	at org.springframework.boot.web.reactive.context.ReactiveWebServerApplicationContext.finishRefresh(ReactiveWebServerApplicationContext.java:83)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:553)
	at org.springframework.boot.web.reactive.context.ReactiveWebServerApplicationContext.refresh(ReactiveWebServerApplicationContext.java:61)
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759)
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:327)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243)
	at com.xxx.xxx.xxx.MainKt.main(PriceApplication.kt:17)
Caused by: java.lang.NoSuchMethodError: org.springframework.plugin.core.PluginRegistry.getPluginOrDefaultFor(Ljava/lang/Object;Lorg/springframework/plugin/core/Plugin;)Lorg/springframework/plugin/core/Plugin;
	at springfox.documentation.spring.web.plugins.DocumentationPluginsManager.createContextBuilder(DocumentationPluginsManager.java:154)
	at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.defaultContextBuilder(AbstractDocumentationPluginsBootstrapper.java:114)
	at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.buildContext(AbstractDocumentationPluginsBootstrapper.java:92)
	at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.bootstrapDocumentationPlugins(AbstractDocumentationPluginsBootstrapper.java:83)
	at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper.start(DocumentationPluginsBootstrapper.java:94)
	at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:181)
	... 14 common frames omitted
Process finished with exit code 1

[MaksimOrlov]

Hi, @pstepnowski. It happened due to mismatch spring-plugin-core version

To fix that you can add explicitly version of spring-plugin-core

<dependency>
  <groupId>io.springfox</groupId>
  <artifactId>springfox-swagger2</artifactId>
  <version>3.0.0-SNAPSHOT</version>
  <exclusions>
    <exclusion>
      <groupId>org.springframework.plugin</groupId>
      <artifactId>spring-plugin-core</artifactId>
    </exclusion>
  </exclusions>
</dependency>
<dependency>
  <groupId>io.springfox</groupId>
  <artifactId>springfox-swagger-ui</artifactId>
  <version>3.0.0-SNAPSHOT</version>
</dependency>
<dependency>
  <groupId>io.springfox</groupId>
  <artifactId>springfox-spring-webflux</artifactId>
  <version>3.0.0-SNAPSHOT</version>
  <exclusions>
    <exclusion>
      <groupId>org.springframework.plugin</groupId>
      <artifactId>spring-plugin-core</artifactId>
    </exclusion>
  </exclusions>
</dependency>
<dependency>
  <groupId>org.springframework.plugin</groupId>
  <artifactId>spring-plugin-core</artifactId>
  <version>2.0.0.RELEASE</version>
</dependency>

[pstepnowski]

Amazing thanks @MaksimOrlov !